Nexstim Navigated Brain Stimulation (NBS) 6 System (NBS6)

The Nexstim NBS 6 System is a non-invasive repetitive transcranial magnetic stimulation (rTMS) device that delivers magnetic pulses to the prefrontal cortex to treat Major Depressive Disorder in adults who have failed antidepressant medication, and as an adjunct for adolescents aged 15–21. It uses MRI-based 3D brain localization and electromyography to target the left dorsolateral prefrontal cortex with continuous position monitoring via a mechanical arm.

The device employs the same treatment protocols as the predicate (120% motor threshold, 10 Hz frequency, 4-second train duration, 75 trains per session, 3000 pulses maximum). It features a Figure-8 focal coil with forced air cooling, biphasic sinusoid waveform, and individual patient motor-threshold calibration. Key difference: the NBS 6 uses direct anatomical targeting via patient MRI versus the predicate's indirect statistical distance method; however, output is calibrated to each patient's individual motor threshold.

IEC 60601-1:2005 (electrical safety), IEC 60601-1-2:2014 (EMC), IEC 60601-1-6:2010 (usability), ISO 10993-1:2009 (biocompatibility), IEC 62304:2006 (software life cycle), and FDA rTMS Class II Special Controls Guidance (26 Jul 11). Bench testing followed predicate device comparison protocols.

Substantial equivalence is based on identical indications, same treatment protocols and stimulation parameters, equivalent coil specifications and magnetic field characteristics, and comparable safety/effectiveness demonstrated through bench testing. Although the NBS 6 uses direct MRI-based targeting versus the predicate's indirect statistical targeting, both systems calibrate output to individual patient motor threshold, resulting in clinically equivalent treatment. No new safety or effectiveness questions are raised.